1. Field of the Invention
The present invention relates to devices for sensing the relative position between the device and a surface, through the use of contacting probes which extend from the device to the surface.
2. Prior Art
For some time, there has been a need for a device which can sense the relative perpendicularity of the device to a surface, and/or the relative angularity of the device to a surface, and which provides an immediate visual indication of the relationship of the device to the surface with sufficient information to permit an operator to manually adjust the orientation of the device, or the surface, to obtain the desired perpendicularity or angularity, as the case may be. Such a device is needed which is also easily portable and relatively inexpensive and easily adaptable to various uses without requiring major changes in its construction.
In addition to the above described desirable features, it is also desirable in certain industries to have a device which can sense the distance from the device to the surface so that the device is not only positioned perpendicular or at a desired angle to the surface, but is also at the required distance from the surface. It is further desirable to provide means for locating the device at a precise point on the surface through lateral movement of the device or the surface. Such devices would have major uses in establishing exact drilling locations, for example, and for use in "teaching" industrial robots which are capable of remembering the location of a position in space once the robot has been removed to that location.
Presently it is a common practice to teach such robots by bringing the robot arm into approximate alignment with the surface, through visual observations and utilizing the driving mechanism of the robot. Then, while the robot arm drive operator continues to move the arm into a more precise orientation relative to the surface, an assistant constantly measures and checks the progress and advises the robot operator of the direction and amount of movement which he feels is necessary in order to bring the robot into the desired exact location. This takes considerable labor and is extremely tedious and time consuming when a multitude of such locations are to be programmed into the robot before it performs its actual intended operation on the surface.